This invention relates generally to a connecting rod used for connecting reciprocating and rotating members in reciprocating piston machines such as internal combustion engines and compressors. More specifically, the invention is directed to a connecting rod design for use in reciprocating piston compressors to lubricate and cool the wrist pin and piston.
Connecting rods for compressors are generally designed with a piston pin ring portion and a crankshaft ring portion connected by an intermediate portion which is integral to the outer periphery of each ring portion. The piston ring portion has a bore for rotatably receiving a piston wrist pin, and the crankshaft ring portion has a bore for rotatably receiving the crankshaft. Each ring portion is reinforced at the connecting area contiguous with the intermediate portion.
Various types of connecting rods include passages therein for transmitting lubricating fluid from the crankshaft ring portion of the rod to the piston ring portion to lubricate and cool the wrist pin during operation of the compressor. Generally, it is desired to provide sufficient lubricant to the wrist pin to lubricate the load bearing areas and to transfer heat away therefrom. Efforts are continuously directed toward increasing the rate of cooling of the piston for more efficient compressor and engine performance.